Add keymap tests

lua/cmp/utils/keymap_spec.lua

@@ -16,4 +16,27 @@ describe('keymap', function()
     assert.are.equal(keymap.escape('<C-d><C-f>'), '<LT>C-d><LT>C-f>')
     assert.are.equal(keymap.escape('<LT>C-d>'), '<LT>C-d>')
   end)
+
+  it('_evacuate', function()
+    local s = function(cmd, keys, buf)
+      spec.before()
+      vim.cmd(cmd)
+      local existing = vim.tbl_filter(function(map)
+        return map.lhs == keys
+      end, keymap._getmaps('i'))[1] or {
+        lhs = keys,
+        rhs = keys,
+        expr = 0,
+        nowait = 0,
+        noremap = 1,
+      }
+      local fallback = keymap._evacuate('i', existing)
+      vim.api.nvim_feedkeys('i' .. keymap.t(fallback), 'x', true)
+      assert.are.same(vim.api.nvim_buf_get_lines(0, 0, -1, true), buf)
+    end
+    s([[]], '(', { '(' })
+    s([[imap <expr> ( '<C-r>="("<CR>']], '(', { '(' })
+    s([[imap ( (]], '(', { '(' })
+  end)
+
 end)